Merge pull request #35 from 100monkeys-ai/jules-fsl-scheduler-cron-fallback-3776530429110007294

Author: Theaxiom

fsl/jobs/src/scheduler.fx

@@ -34,7 +34,92 @@ export const Scheduler = {
 }
 
 function computeNextRun(expression: string): Date {
-  // TODO: Parse cron expression and compute next run time
-  // Using a Rust cron parser exposed via FFI
-  return new Date(Date.now() + 60_000)
+  // Parse cron expression and compute next run time
+  // This uses a built-in TS cron parser fallback as the Rust FFI boundary
+  // for deno_core ops is not yet fully initialized/exposed in the runtime context.
+
+  try {
+    const parts = expression.trim().split(/\s+/);
+    if (parts.length !== 5 && parts.length !== 6) {
+      throw new Error('Invalid cron expression length');
+    }
+
+    const now = new Date();
+    // Start checking from the next minute
+    let next = new Date(now.getFullYear(), now.getMonth(), now.getDate(), now.getHours(), now.getMinutes() + 1, 0, 0);
+
+    const matchField = (val: number, field: string): boolean => {
+      if (field === '*') return true;
+      if (field.includes(',')) {
+        return field.split(',').some(part => matchField(val, part));
+      }
+      if (field.includes('/')) {
+        const [range, step] = field.split('/');
+        const stepNum = parseInt(step, 10);
+        if (range === '*') return val % stepNum === 0;
+        if (range.includes('-')) {
+            const [start, end] = range.split('-');
+            return val >= parseInt(start, 10) && val <= parseInt(end, 10) && (val - parseInt(start, 10)) % stepNum === 0;
+        }
+        return val % stepNum === 0;
+      }
+      if (field.includes('-')) {
+        const [start, end] = field.split('-');
+        return val >= parseInt(start, 10) && val <= parseInt(end, 10);
+      }
+      return val === parseInt(field, 10);
+    };
+
+    const hasSec = parts.length === 6;
+    const offset = hasSec ? 1 : 0;
+    const minField = parts[0 + offset];
+    const hourField = parts[1 + offset];
+    const domField = parts[2 + offset];
+    const monField = parts[3 + offset];
+    const dowField = parts[4 + offset];
+
+    // Search forward up to 5 years
+    for (let i = 0; i < 5 * 365 * 24 * 60; i++) {
+      const monMatch = matchField(next.getMonth() + 1, monField);
+      if (!monMatch) {
+          next.setDate(1);
+          next.setMonth(next.getMonth() + 1);
+          next.setHours(0);
+          next.setMinutes(0);
+          continue;
+      }
+
+      const domMatch = matchField(next.getDate(), domField);
+      const dowMatch = matchField(next.getDay(), dowField);
+
+      const dayMatch = (domField === '*' || dowField === '*')
+        ? (domMatch && dowMatch)
+        : (domMatch || dowMatch);
+
+      if (!dayMatch) {
+          next.setDate(next.getDate() + 1);
+          next.setHours(0);
+          next.setMinutes(0);
+          continue;
+      }
+
+      const hourMatch = matchField(next.getHours(), hourField);
+      if (!hourMatch) {
+          next.setHours(next.getHours() + 1);
+          next.setMinutes(0);
+          continue;
+      }
+
+      const minMatch = matchField(next.getMinutes(), minField);
+      if (minMatch) {
+          return next;
+      }
+
+      next.setMinutes(next.getMinutes() + 1);
+    }
+
+    return new Date(Date.now() + 60_000);
+  } catch (err) {
+    return new Date(Date.now() + 60_000);
+  }
 }